Expendable ammonia noisemaker



June 11, 1963 .1. A. GRAND ETAL 3,093,107

EXPENDABLE AMMONIA NOISEMAKER Filed Jan. 25, 1945 me/ww JOSEPH A. GRAND ROMAN R.MILLER United States Patent Oftiee 3,0937 Patented June l1, 1963 3,093,107 EXPENDABLE SNIA NOESEMAKER Joseph A. Grand, Washington, D.C., and Roman R.

Miller, Silver Spring, Md. (both Naval Research Laboratory, Anacostia Station, Washington 25, D.C.)

Filed lan. 25, 1945, Ser. No. 574,603 9 Claims. (Ci. 116-27) (Granted under Title 35, US. Code (1952), sec. 266) The present invent-ion relates to methods of and means for the generation of underwater sound, particularly the generation of underwater sound by the collapse of vapor bubbles through expendable means and useful as a counter measure against .acoustic torpedoes and mines, or an underwater sound beacon or the like.

In the generation of underwater sound by collapse of vapor bubbles the pressure at which the vapor must be injected into the surrounding body of water Iand the volurne necessary in order to produce sound of an adequate level of intensity, demands a large capacity high pressure source, a requirement ordinarily unobtainable in a readily wieldable compact embodiment such as would be necessary for a practical expendable device especially where such is to be used as a counter-measure.

It is there-tore an object `ot the present invention to provide such a source in a form compact and readily wieldable for launching into the water by one or a crew of a few men and operable fully independently of the mother ship after being launched.

An important phase of this invention is the discovery that the vapors of gaseous substances readily soluble in water such as ammonia, hydrogen chloride and sulfur dioxide, which may be produced much more readily and with lighter apparatus than steam, may be used very effectively in the production of underwater sound by collapse of vapor bubbles.

Another object is the provision of a large capacity high pressure source of vapor highly eect-ive in the production of underwater sound by the collapse of vapor bubbles due to rapid solution of the vapor in a surrounding body of water embodied in a device which, together with other elements constituting a complete expendable underwater sound generator, shall be light, compact, sturdy and capable of being stored for indefinite periods of time in condition for being very readily and quickly primed for use.

A further object is the provision in an underwater device of means for supplying an adequate quantity of heat of evaporation to a body of liquid gas at a controlled, variable rate of application whereby to avoid undue lag in the attainment of substantially full operating pressure and rate of supply and to maintain adequate pressure and rate of supply throughout the operating period.

Various other objects and advantages of the invention will become apparent upon a perusal of the following specification and the drawings accompanying the same.

In the drawings: FIG. l is a side elevation partly in section showing the device in stored condition. tFlG. 2 is an enlarged sectional view of the blow-off patch holding element. FIG. 3 is a small scale View showing the device in operative position in a body of water.

The device comprises in general a container for storage of the vapor supply in the form of a liquitied gas 111, in the present instance liquid ammonia, heating means 12 in the form of a substance capable of generating heat upon contact with water; vapor supply pipe v13; pressure control devices 14, 15 and 16 and a distributing nozzle 17, the whole assemblage being contained in a storage casing 18 together with a supporting cable 19 tor connecting the noise generating device with the storage case for use of the latter as a tio-at when the whole is launched into the water. In operation in a body of water, the whole assemblage assumes the position shown in FIG. 3 in which the parts are inverted with respect to their position in FIG. 1. As shown in =FIG. 3, the device consists of the three main parts, a lloating part 18, a submergible part consisting of the underwear noise making equipment, and means 19 for suspending the submergible part from the oating part in predetermined submerged position. The distributing nozzle 17 may be of any known or other suitable form capable of distributing the gas or vapor into a surrounding body of water in the form of small bubbles, and is preferably of the kind shown and described in the application of Richard F. Post for Expendable Vapor Noise Maker, Serial No. 574,602, tiled January 25, 1945.

The storage container 10 is mounted within a heatercasing 20 wherein it is surrounded by the heating means 12.. Preferable a chemical mixture operable in the presence of a water to generate heat.

Thus pressure within the storage container 10 may be rapidly built up to a desired working pressure and thereafter a supply of heat maintained suicient to compensate for heat absorbed in the evaporation of liquid gas in supplying vapor to the nozzle 17. It will be understood that with the parts inverted from the position of FIG. l into the position of FIG. 3 when in operation, the vapor space 21 will be transferred from the position shown in FIG. l to that shown in dotted lines in FIG. 3, so as to surround the inlet end of the vapor supply pipe 13, with the result that only vapor may pass out through the supply pipe. To prevent escape of vapor before the pressure has built up to a predetermined value, a blow-olf patch holding element 15 is inserted between the blocking valve 14 and pressure reducing valve 16 to interpose a blow-off patch 22 (FIG. 2) in the line of supply to the nozzle.

The lblow-off patch holding element 15 as will be seen from FIG. 2 is in the general form of the usual pipe union and is comprised in the main of a recessed member 23 internally threaded to receive the externally threaded end 24 of a plug member 25. A shouldered portion 26 within the recessed member forms a seat 27 for the blowoli patch disc 22 the valve seat having a sharp shearing inner edge 28. A gasket 29 seals the junction between the plug member and the blow-out patch disc and transmits tfhe pressure evenly over the marginal edge of the blow-out patch disc against the patch disc seat 27. An externally threaded extension 30 on the other end of the plug member connects with the outlet end of the blocking valve 14 while a similarly externally threaded extension 31 on the outer end of the recessed member 23 connects with the automatic pressure reducing valve 16. Thus with the blow-out patch sealed across the connection between the blocking valve and the automatic pressure reducing valve, such connection is sealed against the ow of vapor until the pressure on the inlet side of the blow-olir patch holder 15 increases to a magnitude suicient to force the blow-oli patch against the shearing edges of the seat, shearing out the patch and clearing the passage-way to the pressure reducing valve. In the present embodiment the blow-olf patch is of thin sheet copper of a thickness in the neighborhood of live thousandths of an inch, with a diameter at the shearing edges 2S of the seat of approximately one half inch. It Will be understood of course that the blow-off patch may be made of any known or other suitable material capable of sealing off the vapor under pressure until the shearing pressure is reached. vThus the blow-ofi patch functions as a time delay means of postponing operation until the vapor pressure has built up to a predetermined Working pressure, the delay being determined by two factors, the pressure at which the patch is designed to shear, and the rate at which the pressure builds up.

The automatic pressure reducing valve 16 may be of any known or other suitable form operable automatically to reduce the high pressure delivered to the valve to a lower pressure of given value above ambient pressure, delivering the vapor at such controlled pressure to the distributing nozzle 17. Vapor under pressure is supplied from a body of liquied gas, -in the present instance, am-

monia, nearly filling the cylinder 10, for example tothelevel 32 so as to allow a vapor space 21 (FIG. 3) around the inner end of the vapor supply pipe 13 when the device in use is inverted with respect to conditions shown in FIG. l. Pressure is built up in the vapor space by the application of heat to the body of liquid ammonia within the cylinder 10 through the cylinder wall from the chemical heating substance 12 surrounding the cylinder 10 in the heater casing 20. Tihis heating casing is in the form of a cylindrical can having in its end walls 33 and 34 a series of vent tubes 35 and 36, and lled with a chemical mixture 12 of any known or other suitable kind capable of generating heat upon contact with Water, preferably a combination of two such mixtures, one a fast operating mixture in relatively small proportion and the other a relatively slow operating mixture in relatively larger proportion and operable in combination to effect first a rapid generation of heat for a relatively short time and later a relatively slower generation of heat for a longer time whereby the pressure is rapidly built up to the desired working pressure, and thereafter maintained at working pressure without substantial increase in pressure. In the present embodiment this is accomplished by a mixture as follows:

NaOH, 5,940 grams, NaZO, 600 grams, Aluminum shavings, 600 grams.

The sodium hydroxide is used in the form of lenticular pellets of approximately a quarter inch in diameter and one eighth inoh thick. The sodium oxide is used in the form of cylindrical pellets of approximately one-half inch in length by a little less than one-eighth inch in diameter. With the mixture thus formed the reaction of the sodium oxide with rapid production of heat continues for about seconds after which the sodium hydroxide formed by the action of the sodium oxide with the water, together with the initial supply of sodium hydroxide in pellet form, continues to react with the aluminum turnings to Igenerate heat at the lower rate. Readily removable sealing strips 37 and 38, in the present embodiment strips of adhesive cellophane, close the outer ends of the vent tubes 35 and 35. To prevent loss of the heating chemicals and to prevent the vent from being clogged up by the pellets of heating chemicals, screen diaphrams 39 and 40 are placed within the casing 20 at either end between the charge of chemical mixture 12 and the inner end of the vent tubes and spaced from the vent tubes by means of suitable spacing rings 41 and 42 maintaining the screens out of contact with the vent tubes thus assuring a continuous flow of water and gaseous end-products through the screen to the vent tubes, even should a portion of the screen opposite the vent tubes become clo-gged. The vent tubes 36 which in operation functions as outlets for water vapor and gas are greater in number than vent tubes 35 which in opera-tion function as inlet openings for water. In the present embodiment there are eight of the vent tubes 36 and four of the vent tubes 35. A thermal insulating jacket 43 in the form of an adhering coating of plastic material covers the entire surface of the heater casing 20.

The device is stored in the storage casing 18 as shown in FiIG. l with one end of the supporting cable 19 terminating in the hook 44 secured through sudh hook to a supporting eye 45 in the end wall 34 with the' remainder of the cable extending up along the inner side of the casing and stored in a roll near the top of the casing so that the cable may be used to aid in withdrawing the noise generating device from th'e casing, the Vfree end of the cable 19 terminating in a fastening hook 46. -A lid 47 clamped on by means of clamps 48 covers the storage casing and is provided with a suitable handle 49 for ready handling of the casing and for attachment of the cable hook 46 for use of the empty casing as a lloat. A more complete understanding of the device and the cooperative relation of its 'constituent parts will be had from the description of operation which follows:

In operation, the lid clamps 48 are released, the lid removed and the noise generating device withdrawn from the casing with the aid of the distributing nozzle 17 and the supporting cable 19. The case now being empty the lid is replaced and clamped on with the clamps 48 whereupon the cable hook 46 at the fnee end of the cable is hooked on to the handle 49. 'Ilhe empty storage case 17 being now sealed except for the very small bleed openings 50 and 51, is ready for use as a supporting float for the noise generating device. The ldevice is now primed for operation by opening the blocking valve 14 and withdrawing the sealing'stripsV 37 and 38, and is immediately launched into the body of water into which it is to be used.

The noise ,generating device entering the body of water sinks to the depth determined by the length of supporting cable 19, the upper end of which is maintained near the surface by the floating, empty storage casing 18. The assemblage now assumes the position indicated in FIG. 3 where it will be noticed that the sound generating device is in a position inverted with respect to that shown in FIG. l. This of course causes the body of liquid gas to gravitate toward the now lower end of the gas storage cylinder 10 placing the vapor space 21 at the closed end of the cylinder above the inlet of the vapor outlet pipe 13. Water now entering the inlet vent tubes 35 rises upwardly mixing with the chemical mixture 11 whereupon chemical action takes place resulting in first a very rapid generation of heat for a short period of 'time followed by a slower generation of heat for a longer period of time the gaseous end products rising out of the interior of the heater escaping through outlet vent'tubes 36. During the rapid heating period of this operation, the liquid ammonia 11 in the storage tank 10 is rapidly heated raising the pressure in the vapor space around the inlet end of the Vapor supply pipe 13 until in about 50 Seconds or less the pressure reaches approximately 600 pounds per square inch whereupon the central portion of the blow-olf patch is sheared out along the edge 28y and either blown clear of the edge into the passage between the blow-off patch holder and the pressure reducing valve in a substantially unobstructing position, or severed from the marginal portion on the seat 27 except for a small portion by which it may be held, but in a position to permit only a negligible resistance to the flow of operating vapor. Thus the blow-off patch functions both as a time delay to postpone operation during proper positioning of the device in the water relative to the mother ship, and as a means for preventing the escape of vapor before the proper operating pressure has been reached. The vapors now passing to the automatic reduction valve are acted on by such valve to pass them on to the distributing nozzle at a pressure reduced to a given amount above ambient pressure, in the present instance a difference in the neighborhood of pounds per square inch. The vapor delivered to the nozzle at this pressure is distributed into the water in the form of discrete bubbles which, rapidly collapsing, generate the underwater'noise or sound desired.

Shortly after the building up of the Vapor pressure to the maximum determined by operation of the blow-off patch, the rapid heating phase of the cycle ceases, followed by the continuing action of the NaOH on the aluminum in the presence of water to maintain a relatively slower application of heat to the .liquid ammonia suicient to keep the pressure up to a point well above the working pressure desired at the nozzle, for an indefinite time according to the storage capacity of the device. After a time amply sufficient for completion of a full operation the water which in the meantime has been very slowly entering the storage casing through the bleed holes reaches an amount sufficient to sink the casing 18 so that the entire assemblage is lost to sight.

While but one specific embodiment of the invention has been shown and described herein for the sake of disclosure, it is to be understood that the invention is not limited to such specific embodiment but contemplates all such modifications and variants thereof as fall fairly Within the scope of the appended claims.

The invention described herein may be manufactured and used by or for the Government of the United States of America for Government purposes without the payment of any royalty thereon or therefor.

What is claimed is:

1. An expendable underwater sound generating device comprising a floating part and a submergible part, means suspending the submergible part from the floating part in a predetermined submerged position, said submergible part including a container, a body of liquid gas partially filling the container and leaving a liquid-free gas-filled space above the liquid in the submerged position, means operable upon submergence in a body of water to supply heat to the said body of liquid, a nozzle positioned to be submerged in the water when the device is floated for injecting gas into a surrounding body of water for generating compressional waves by collapse of the gas volume, means forming a gas conducting passage between said space and said nozzle, pressure responsive means for connecting said space with the nozzle upon attainment of a given pressure in said space, and an automatic pressure regulating valve connected in said conducting passage between the said pressure responsive means and the nozzle.

2. An expendable underwater sound generating device comprising a floating part and a submergible part, means suspending the submergible part from the floating part in a predetermined submerged position, said submergible part including a container, a body of liquified gas partially filling the container to leave a liquid free, gas filled space in the upper part of the container in the submerged position, a distributing nozzle positioned to be submerged in the water when the device is floated for discharging bubbles of gas into the water for generating compressional waves by collapse of the bubbles, means forming a gasconducting passage between said space and said nozzle, and means positioned to be submerged in the water when the device is floated and operable upon submergence in water t-o supply heat to said container first at a relatively rapid rate and later at a relatively slower rate.

3. An expendable underwater sound generating device comprising a floating part and a submergible part, means suspending the submergible part from the floating part in a predetermined submerged position, said submergible part including a container, a body of liquied gas partially filling the container to leave a liquid free, gas filled space in the upper part of the container in the submerged position, a distributing nozzle positioned to be submerged in the water when the device is floated for discharging bubbles of gas into the water for generating compressional waves by collapse of the bubbles, means forming a gas conducting passage between said space and said nozzle, means normally closing said passage and pressure responsive to open the passage upon attainment of a given pressure in said space and means positioned to be submerged in the water when the device is floated and operable upon submergence in water to supply heat to said container first at a relatively rapid rate and later at a relatively slower rate.

4. An expendable underwater sound generating device comprising a floating part and a submergible part, means suspending the submergible part from the floating part in a predetermined submerged position, said submergible part including a container, a body of liquifled gas partially filling the container to leave a liquid free, gas filled space in the upper part of the container in the submerged position, a distributing nozzle positioned to be submerged in the water when the device is floated for discharging bubbles of gas into ythe water for generating compressional waves by collapse of the bubbles, means forming a gas conducting passage between said space and said nozzle, a mixture of two chemical substances surrounding said container, one a chemical substance operable in the presence of water to effect a relatively rapid generation of heat and the other a chemical substance operable in the presence of water to effect a relatively slower generation of heat, said first substance being in larger proportion than the latter, and means admitting water to said chemical substances when the device is floated.

5. An expendable underwater sound generating device comprising a floating part and a submergible part, means suspending the submergible part from the floating part in a predetermined submerged position, said submergible part including a container, a body of liquified gas partially filling the container to leave a liquid free, gas filled space in the upper part of the container in the submerged position, a distributing nozzle positioned to be submerged in the Water when the device is floated for discharging bubbles of gas into the water for generating compressional waves by collapse of the bubbles, means forming a gas conducting passage between said space and said nozzle, a heater casing having vent openings therein, containing the said liquifled-gas container, a mixture of chemical heating substances surrounding the liquied-gas container, said mixture comprising sodium oxide, sodium hydroxide and comminuted metallic aluminum in the following proportions: sodium oxide 600 grams, sodium hydroxide 5940 grams and aluminum 600 grams, and means admitting water to said chemical substances when the device is 6. An expendable underwater sound generating device comprising a floating part and a submergible part, means suspending the submergible part from the floating part in a predetermined submerged position, said submergible part including a container, a body of liquified gas partially filling the container to leave a liquid free, gas filled space in the upper part of the container in the submerged position, a distributing nozzle positioned to be submerged in the water when the device is floated for discharging bubbles of gas into the water for generating compressional waves by collapse of the bubbles, means forming a gas conducting passage between said space and said nozzle, a heater casing having vent openings therein, containing the said liquified-gas container, a mixture of chemical heating substances surrounding the liquified-gas container, said mixture comprising sodium oxide, sodium hydroxide and comminuted metallic aluminum in the following proportions: sodium oxide 600 grams, sodium hydroxide 5940 grams and aluminum 600 grams, said sodium oxide being in the form of lenticular pellets of approximately onefourth inch in diameter and one-eighth inch thick, and said sodium hydroxide being in the form of cylindrical pellets approximately one-half inch long and one-eighth inch in diameter, and means admitting water to said chemical substances when the device is floated.

7. An expendable underwater sound generating device comprising a floating part and a submergible part, means suspending the submergible part from the floating part in a predetermined submerged position, said submergible part including a container, a body of liquified gas partially filling the container -to leave a liquid free, gas filled space in the upper part of the container in the submerged position, a distributing nozzle positioned to be submerged in the water when the device is floated for discharging bubbles of gas into the water for generating compressional waves by collapse of the bubbles, means forming a gas conducting passage between said space and said nozzle, means normally closing said passage and pressure responsive to open the passage upon attainment of a given pressure in said space, and means positioned to be submerged floated and operable upon in the water when the device is submergence in water to supply heat to said container first at a relatively rapid rate and later at a relatively slower rate.

8. An expendable underwater sound generating device comprising a floating part and a submergible part, means suspending the submergible part from the oating part in a predetermined submerged position, said submergible part including a container, a body of liquied gas partially filling the container to leave a liquid free, gas lled space in the upper part of the container in the submerged position, a distributing nozzle positioned Vto be submerged in the water when the device is floated for discharging bubbles of gas into the Water for generating compressional waves by collapse of the bubbles, means forming a gas conducting passage between said space and said nozzle, a heater casing having vent openings therein, containing the said liquiied-gas container and a mixture of chemical heating substances surrounding the liquied-gas container, said mixture comprising sodium oxide, sodium hydroxide and comminuted metallic aluminum in the following proportions: sodium oxide 600| grams, sodium hydroxide 5940 grams and aluminum 600 grams, said sodium oxide being in the form of lenticular pellets of approximately one-fouth inch in diameter and one-eighth inch thick, and said sodium hydroxide being in the form of cylindrical pellets approximately one-half inch long and one-eighth inch in diameter, together with a blocking valve in said passage between said liquied gas container and said pressure responsive means, an automatic pressure reducing valve connected in said passage between said pressure responsive means and said nozzle, and means admitting water to said chemical substances when the device is floated.

9. An expendable underwater sound generating device comprising a oating part and a submergible part, means suspending the submergible part from the oating part in a predetermined submerged position, said submergib-le part including a storage container, a body of liquied gas partially filling the upper part of the container in the submerged position to leave a liquid free, gas lled space in the storage container, a distributing nozzle positioned to be submerged in the water when the device is floated for discharging bubbles of gas into lthe water for generating compressional Waves 'by collapse of the bubbles, means forming a fluid conducting pass-age between the interior of said Container and the nozzle, a blow-off patch normally closing said passage and rupturable upon the attainment of a given pressure in said space to open said passage, and means positioned to be submerged in the water when the device is floated and operable upon submergence in water to supply heat to said container rst at a relatively rapid rate and later at a relatively slower rate.

References Cited in the file of this patent UNITED STATES PATENTS 568,680 Henderson Sept. 29, 1896 852,646 Blake Mar. 7, 1907 V852,647 Blake Mar. 7, 1907 853,693 Healey May 14, 1907 942,112 Sprecher Dec. 7, 1909 1,010,768 Isaacs Dec. 5, 1911 1,030,456 BroadhurSt June 25, 1912 1,697,199' Martyn Ian. 1, 1929 1,928,226 Todd Sept. 26, 1933 1,969,644 Gavett Aug. 7, 1934 2,211,142 Loudon Aug. 13, 1940 2,271,764 Heil Feb. 3, 1942 v2,289,007 Gessler `Tuly 7, 1942 2,305,796 Seidel Dec. 22, 1942 2,313,215 Bierlee Mar. 9, 1943 2,384,720 Babcock Sept. 11, 1945 2,395,252 Carpenter Feb. 19, 1946 2,402,143 Arenstein June 18, 1946 FOREIGN PATENTS 398,114 Great Britain Sept. 7, 1933 

1. AN EXPENDABLE UNDERWATER SOUND GENERATING DEVICE COMPRISING A FLOATING PART AND A SUBMERGIBLE PART, MEANS SUSPENDING THE SUBMERGIBLE PART FROM THE FLOATING PART IN A PREDETERMINED SUBMERGED POSITION, SAID SUBMERGIBLE PART INCLUDING A CONTAINER, A BODY OF LIQUID GAS PARTIALLY FILLING THE CONTAINER AND LEAVING A LIQUID-FREE GAS-FILLED SPACE ABOVE THE LIQUID IN THE SUBMERGED POSITION, MEANS OPERABLE UPON SUBMERGENCE IN A BODY OF WATER TO SUPPLY HEAT TO THE SAID BODY OF LIQUID, A NOZZLE POSITIONED TO BE SUBMERGED IN THE WATER WHEN THE DEVICE IS FLOATED FOR INJECTING GAS INTO A SURROUNDING BODY OF WATER FOR GENERATING COMPRESSIONAL WAVES BY COLLAPSE OF THE GAS VOLUME, MEANS FORMING A GAS CONDUCTING PASSAGE BETWEEN SAID SPACE AND SAID NOZZLE, PRESSURE RESPONSIVE MEANS FOR CONNECTING SAID SPACE WITH THE NOZZLE UPON ATTAINMENT OF A GIVEN PRESSURE IN SAID SPACE, AND AN AUTOMATIC PRESSURE REGULATING VALVE CONNECTED IN SAID CONDUCTING PASSAGE BETWEEN THE SAID PRESSURE RESPONSIVE MEANS AND THE NOZZLE. 